1. Field of the Invention
The invention relates to the use of flupirtine or its salts as medicaments for the prophylaxis and therapy of disorders with an unphysiologically high cell death rate.
2. Background Information
Flupirtine is a known centrally active, non-opiate analgesic which has been introduced in Germany and is licensed, inter alia, for the therapy of neuralgia, pain in wear-related joint disorders, headaches and post-operative pain.
Flupirtine displays its analgesic actions by means of other mechanisms of action than the opiate/opioid analgesics (Nickel, B., Postgrad, Med. J. 63 (Suppl.3), 19 (1987); Szelenyi, I., Nickel B., Borbe, H. O., Brune K., Br. J. Pharmacol. 143,89 (1989)). In electrophysiological investigations, it has been shown that flupirtine is able to intervene both on the supraspinal and on the spinal level in the nociceptive process (Carlsson, K. H., Jurna, I., Eur. J. Pharmacol. 143,89 (1987); Bleyer, H., Carlsson, K. H., Erkel, H. J., Jurna, I., Eur. J. Pharmacol. 151,259 (1988); Nickel, B., Aledter, A., Postgrad, Med. J. 63 (Suppl.3) 41 (1987)).
Besides good analgesic properties, flupirtine has muscle-relaxant properties, so flupirtine can also be employed for the treatment of muscle sprains or in disorders which are based on muscle sprains (DE 40 22 442).
In addition, during investigations of the muscle-relaxant action of flupirtine in the rat, it was found that the flupirtine action can be inhibited by the excitatory amino acid N-methyl-D-aspartate (NMDA). On the basis of this NMDA-antagonistic action, flupirtine is also suitable for the treatment of NMDA-mediated CNS disorders, such as, for example, cerebral ischemia, neurodegenerative disorders, [sic] epileptic fits (DE 43 27 516).
Looked at chemically, flupirtine is 2-amino-3-ethoxycarbonylamino-6-(p-fluorobenzylamino)pyridine.
The synthesis of flupirtine and its pharmaceutically utilizable salts is described in the patents DE 17 95 858, DE 31 33 519 and DE 34 16 609.